Override primitive serialization and deserialization of payload

Applies To: # OData Webapi for Webapi supported OData AspNet WebApi V6

Since ODataLib 6.12.0, it supports to customize the payload value converter to override the primitive serialization and deserialization of payload.

New public API

The new class ODataPayloadValueConverter provides a default implementation for value conversion, and also allows developer to override by implementing ConvertFromPayloadValue and ConvertToPayloadValue.

public class Microsoft.OData.Core.ODataPayloadValueConverter {
	public ODataPayloadValueConverter ()

	public virtual object ConvertFromPayloadValue (object value, Microsoft.OData.Edm.IEdmTypeReference edmTypeReference)
	public virtual object ConvertToPayloadValue (object value, Microsoft.OData.Edm.IEdmTypeReference edmTypeReference)
}

New helper functions to set converter to model so the new converter can be applied:

  public static void SetPayloadValueConverter (Microsoft.OData.Edm.IEdmModel model, Microsoft.OData.Core.ODataPayloadValueConverter converter)
  public static Microsoft.OData.Core.ODataPayloadValueConverter GetPayloadValueConverter (Microsoft.OData.Edm.IEdmModel model)
}

Sample

Here we are trying to override the default converter to support the "R" format of date and time. It is quite simple.

1. Define DataTimeOffset converter

internal class DateTimeOffsetCustomFormatPrimitivePayloadValueConverter : ODataPayloadValueConverter
{
    public override object ConvertToPayloadValue(object value, IEdmTypeReference edmTypeReference)
    {
        if (value is DateTimeOffset)
        {
            return ((DateTimeOffset)value).ToString("R", CultureInfo.InvariantCulture);
        }

        return base.ConvertToPayloadValue(value, edmTypeReference);
    }

    public override object ConvertFromPayloadValue(object value, IEdmTypeReference edmTypeReference)
    {
        if (edmTypeReference.IsDateTimeOffset() && value is string)
        {
            return DateTimeOffset.Parse((string)value, CultureInfo.InvariantCulture);
        }

        return base.ConvertFromPayloadValue(value, edmTypeReference);
    }
}

2. Set converter to model

model.SetPayloadValueConverter(new DateTimeOffsetCustomFormatPrimitivePayloadValueConverter());

Then DateTimeOffset can be serialized to Thu, 12 Apr 2012 18:43:10 GMT, and payload like Thu, 12 Apr 2012 18:43:10 GMT can be deserialized back to DateTimeOffset.